korg/linux
0
0
Fork 0
mirror of https://mirrors.bfsu.edu.cn/git/linux.git synced 2024-12-14 06:24:53 +08:00
Code Issues Packages Projects Releases Wiki Activity

KVM: arm64: Improve debug register save/restore flow

Browse Source 
Instead of having multiple calls from the world switch path to the debug
logic, each figuring out if the dirty bit is set and if we should
save/restore the debug registers, let's just provide two hooks to the
debug save/restore functionality, one for switching to the guest
context, and one for switching to the host context, and we get the
benefit of only having to evaluate the dirty flag once on each path,
plus we give the compiler some more room to inline some of this
functionality.

Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
This commit is contained in:
Christoffer Dall 2017-10-10 20:10:08 +02:00 committed by Marc Zyngier
parent 5742d04912
commit 014c4c77aa
3 changed files with 42 additions and 30 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/arm64/include/asm/kvm_hyp.h
View File

@ -138,14 +138,8 @@ void __sysreg_restore_guest_state(struct kvm_cpu_context *ctxt);
void __sysreg32_save_state(struct kvm_vcpu *vcpu);
void __sysreg32_restore_state(struct kvm_vcpu *vcpu);
void __debug_save_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt);
void __debug_restore_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt);
void __debug_cond_save_host_state(struct kvm_vcpu *vcpu);
void __debug_cond_restore_host_state(struct kvm_vcpu *vcpu);
void __debug_switch_to_guest(struct kvm_vcpu *vcpu);
void __debug_switch_to_host(struct kvm_vcpu *vcpu);
void __fpsimd_save_state(struct user_fpsimd_state *fp_regs);
void __fpsimd_restore_state(struct user_fpsimd_state *fp_regs);

56
arch/arm64/kvm/hyp/debug-sr.c
View File

@ -110,16 +110,13 @@ static void __hyp_text __debug_restore_spe_nvhe(u64 pmscr_el1)
write_sysreg_s(pmscr_el1, SYS_PMSCR_EL1);
}
void __hyp_text __debug_save_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt)
static void __hyp_text __debug_save_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt)
{
u64 aa64dfr0;
int brps, wrps;
if (!(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY))
return;
aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
brps = (aa64dfr0 >> 12) & 0xf;
wrps = (aa64dfr0 >> 20) & 0xf;
@ -132,16 +129,13 @@ void __hyp_text __debug_save_state(struct kvm_vcpu *vcpu,
ctxt->sys_regs[MDCCINT_EL1] = read_sysreg(mdccint_el1);
}
void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt)
static void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
struct kvm_guest_debug_arch *dbg,
struct kvm_cpu_context *ctxt)
{
u64 aa64dfr0;
int brps, wrps;
if (!(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY))
return;
aa64dfr0 = read_sysreg(id_aa64dfr0_el1);
brps = (aa64dfr0 >> 12) & 0xf;
@ -155,10 +149,12 @@ void __hyp_text __debug_restore_state(struct kvm_vcpu *vcpu,
write_sysreg(ctxt->sys_regs[MDCCINT_EL1], mdccint_el1);
}
void __hyp_text __debug_cond_save_host_state(struct kvm_vcpu *vcpu)
void __hyp_text __debug_switch_to_guest(struct kvm_vcpu *vcpu)
{
__debug_save_state(vcpu, &vcpu->arch.host_debug_state.regs,
kern_hyp_va(vcpu->arch.host_cpu_context));
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
struct kvm_guest_debug_arch *host_dbg;
struct kvm_guest_debug_arch *guest_dbg;
/*
* Non-VHE: Disable and flush SPE data generation
@ -166,15 +162,39 @@ void __hyp_text __debug_cond_save_host_state(struct kvm_vcpu *vcpu)
*/
if (!has_vhe())
__debug_save_spe_nvhe(&vcpu->arch.host_debug_state.pmscr_el1);
if (!(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY))
return;
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
__debug_save_state(vcpu, host_dbg, host_ctxt);
__debug_restore_state(vcpu, guest_dbg, guest_ctxt);
}
void __hyp_text __debug_cond_restore_host_state(struct kvm_vcpu *vcpu)
void __hyp_text __debug_switch_to_host(struct kvm_vcpu *vcpu)
{
struct kvm_cpu_context *host_ctxt;
struct kvm_cpu_context *guest_ctxt;
struct kvm_guest_debug_arch *host_dbg;
struct kvm_guest_debug_arch *guest_dbg;
if (!has_vhe())
__debug_restore_spe_nvhe(vcpu->arch.host_debug_state.pmscr_el1);
__debug_restore_state(vcpu, &vcpu->arch.host_debug_state.regs,
kern_hyp_va(vcpu->arch.host_cpu_context));
if (!(vcpu->arch.debug_flags & KVM_ARM64_DEBUG_DIRTY))
return;
host_ctxt = kern_hyp_va(vcpu->arch.host_cpu_context);
guest_ctxt = &vcpu->arch.ctxt;
host_dbg = &vcpu->arch.host_debug_state.regs;
guest_dbg = kern_hyp_va(vcpu->arch.debug_ptr);
__debug_save_state(vcpu, guest_dbg, guest_ctxt);
__debug_restore_state(vcpu, host_dbg, host_ctxt);
vcpu->arch.debug_flags &= ~KVM_ARM64_DEBUG_DIRTY;
}

6
arch/arm64/kvm/hyp/switch.c
View File

@ -305,7 +305,6 @@ int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)
guest_ctxt = &vcpu->arch.ctxt;
__sysreg_save_host_state(host_ctxt);
__debug_cond_save_host_state(vcpu);
__activate_traps(vcpu);
__activate_vm(vcpu);
@ -319,7 +318,7 @@ int __hyp_text __kvm_vcpu_run(struct kvm_vcpu *vcpu)
*/
__sysreg32_restore_state(vcpu);
__sysreg_restore_guest_state(guest_ctxt);
__debug_restore_state(vcpu, kern_hyp_va(vcpu->arch.debug_ptr), guest_ctxt);
__debug_switch_to_guest(vcpu);
/* Jump in the fire! */
again:
@ -416,12 +415,11 @@ again:
__fpsimd_restore_state(&host_ctxt->gp_regs.fp_regs);
}
__debug_save_state(vcpu, kern_hyp_va(vcpu->arch.debug_ptr), guest_ctxt);
/*
* This must come after restoring the host sysregs, since a non-VHE
* system may enable SPE here and make use of the TTBRs.
*/
__debug_cond_restore_host_state(vcpu);
__debug_switch_to_host(vcpu);
return exit_code;
}